Larry Snider writes:
> I've been off the list for the past couple of years as the Triumphs
> went on hold in favor of other pursuits, but now I'm reassembling the
> 1969 Spitfire I disassembled some four years ago.
> I have most of the engine back together, but my question is about the
> camshaft timing.
> The Haynes book says "It's easy to get the camshaft 180 degrees off".
>
> According to my calculations, the camshaft turns once for each two
> revolutions of the crank. So if the cam sprocket is 180 degrees off,
> doesn't that simply mean that the next revolution of the crank is TDC
> on the compression stroke?
>
> Once the timing gears are covered, no one can see where the timing
> mark on the cam sprocket is anyway, and we always find TDC on the
> compression stroke by observing the behavior of the valves, so if the
> timing mark on the cam sprocket is 180 off, how can it matter?
>
> I'll bet I'm missing something here...
>
> Anyway, I want to make SURE I have the timing stuff right before I go
> on...
>
> Thanks!
>
> Larry in St. Louis
Welcome back Larry. We missed you at the Xmas party.
180 degrees off. Was this in in the distributer install part?
You are right. The crank goes up and down and up and down. It
doesn't know one up form the other. But setting the crank to TDC
and plugging in the dizzy will get you there about 50% of the time.
When they say "180 degrees", 180 degrees of what? The camshaft or
the crankshaft? Anyway the exhaust and intake valves for cylinder
#1 or #4 should rock as you turn through TDC. Cylinders #2 and #3
should rock through BDC on the crank.
Dave (closer to St. Louis than Larry)
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